So today, I installed the new hose, MAKE SURE TO USE A BREAKER BAR when removing the old hose!
so I installed the new hose and drove it, the leak has been fixed but the fuel consumption hasn't stopped. So tomorrow I will be renting out a fuel pressure tester at Autozone and check out the pressure out put of the fuel pump. If that doesn't fix it, hopefully I can still return the airtex pump and buy one from the dealer and hope it gets fixed.
Sorry to hear. I felt sure leakage was going to explain your excessive fuel consumption. It is very hard for me to believe you are getting less than 5mpg... and not experiencing fuel-rich smoking and/or plug fouling.
Have you even read MY POST ?
I had a 280 se 4.5, same engine and injection system. It was dumping gas like that (like yours) through a couple of injectors that did not close !!!
NO BLACK SMOKE either .
I got about 6 miles a gallon (back then @$1 / gallon).
It drove like a bat out of hell at times....
FYI
over and out for me................
I have no experience with this Airtex fuel pump, and it would be my first suspect that it is not working good with the Djet. If you check your Djet injectors, feel with your finger around the injector seals, i can imagine your injectors are swimming in fuel if the sealings are brittle. Fuel will not drop to the ground because the heat in the engine bay will vaporize it.
If this is the case and you are driving the car, which i assume you do, because you say consumtion has not changed, that is very dangerous!
Are all cylinders firing?
So I checked the oil today, and the oil is mixed with fuel. How did that happen? I remember when I turned the vehicle on yesterday, it was blowing out black paint like spray at the exhaust. The car is running a bit rough as well. Anyone got any thoughts on this? and I think my fuel pump is working properly, just having weird issue with the fuel in the oil.
You're pushing a lot of fuel into the cylinder by the injectors being stuck open or being forced open by too much fuel pressure supplied by pump+regulator. Extra fuel is leaking to the crankcase.
Black sooty exhaust is a symptom of an overly rich mixture, but you knew that because your mpg was 5.
I "thought" I had responded to this thread this morning. I guess I forgot to submit the message
Summary:
Before you blame the pump,
- Check that injectors and cold start valve do not leak excessively - Section 7.4 of manual (in EGermanica) gives leak down rate - I think my car takes about 5min to leak down to 22psig. (I have full time dash gauge)
- Check for external leaks around injectors as Judy has suggested. You should be able to smell gas if the hoses are leaking.
- Check fuel pressure while you are testing injectors - If it is not at 30 +/- 1psig, adjust Fuel pressure regulator until it is.
- Make sure your return line to the tank is not blocked (if fuel pressure is high)
- Check plugs and perhaps post photos of them. They should not be sooty or wet. If one or two are, those could be the bad injectors
- Have a look at injectors - Make sure the pintle covers are in place and perhaps do a spray test as outlined in manual.
- If plugs are sooty or wet, you may have a problem with the trigger points being worn. They can't be adjusted easily. More on this available if you get this far because this WAS the problem with my car when it ran rich.
You're pushing a lot of fuel into the cylinder by the injectors being stuck open or being forced open by too much fuel pressure supplied by pump+regulator. Extra fuel is leaking to the crankcase.
Black sooty exhaust is a symptom of an overly rich mixture, but you knew that because your mpg was 5.
Is something like that only possible with worn piston rings or can the gas even drip into the crankcase with with new/good piston rings?
It all depends on how much fuel is being dumped into the cylinders. In this case the car was still driveable but I have seen cases when the car would load-up on Idle, fill the crankcase with fuel and even have raw fuel comming out the tail pipe. That was scary !!
And get the problem fixed. My GF had a '73 Camaro 2 bbl. carb. It died and she called me after she had it towed to a service station. Mechanic there said it was flooding out due to a stuck or damaged float. It was still under warranty so I advised her to call the dealer. The dealer had it towed to their shop. The next day they went to move it into a service bay. It exploded when they tried to start it and blew the valve covers off damaging the hood. All covered of course and kind of funny now.
Don't try to start it anymore untill you change the oil and find the problem!!!!!!!!!!!!
update: didn't have time to check the pressure on the pump, tried to return it to Intex Auto and they told me I'll have to wait for the manager to come back on Monday for me to do a refund, since I don't want to get another Airtex fuel pump.
Then I ordered a used fuel pump from Anderson, CA that'll be in on Tuesday.
As of now, I wanna drain the oil out because its filled with fuel, but I can't seem to find the size for the drain plug, what size is the drain plug? thanks in advance!
okay, so I've been browsing the web trying to find how to remove the oil filter housing. I just found out that the housing is hold on by the oil filter housing bolt that's underneath, which is a size 13mm open socket... geez... so confusing.
so the drain plug is 14mm hex, and the oil filter housing is a 13mm socket.
So I'm still waiting on the Fuel pump from that used car place in Anderson, CA.
So I have a theory about whats wrong here, I assume the Airtex fuel pump I got was designed for 76 and above Mercedes benz 450SL. The reason is because the Airtex fuel pump looks exactly like the 76+ 450SL.
The other reason the fuel pump is pumping out too much pressure because I felt it by the hose that was by the fuel pump, so the pressure its putting out is too high so the fuel is leaking through the o-rings of the piston.
The only way to tell is when I receive the fuel pump and replace the old one and see if it changes. Thats all theory, so lets hope I am right. I gotta call them tomorrow and see where's the fuel pump so I can install it.
thank you all for your knowledge that you've given me, being on this forum makes me know more about the car than before. Thanks all.
Yes, and yes.
I don't think the original poster ever had the car running before putting in this fuel pump.
I am also assuming that the original injectors are still in that car as was his (original) fuel pump.
Just a picture I am drawing in my head as this poster is describing a rubber fuel line cracking and crumbling (could that have been the original one from 1973 ? / that's 38 years old ?)
Now I was talking about (fuel-)thinned out oil before he mentioned it.
The injector(s) are stuck open ,because of either the trigger points or faulty injectors...
That would be a couple of steps down the line, from where he is.
He needs to check , if they are !
The fuel gets in the oil only one way assuming the original poster put the gas nozzle in the right place, the last time at the gas station.
So far I am waiting to be proven wrong with my suggestions first...............
I maybe skipping a couple of steps and not write down every thought in my process, but I am not a fast typer and the basic Idea is there......
I wouldn't be answering the post, if I didn't think I could help.
I just feel the original poster is skipping my suggestion for whatever reason.....
Enough said.
I am sure somebody will point him in the right direction, I am out.
LOL!!! Now in the fella's defense, just because he's not a mechanic doesn't mean he'd put the gas anywhere other than the fuel tank. But that was funny to read.
I thought I read that the original poster was getting ~12mpg before. The car must now be running if they were able to calculate 5 mpg too. Right? So I assume this car was running.
The good thing for me... I'm just getting MY car running and I'm getting about 5 mpg (which includes all city driving and lots of idling in the driveway while working on the car). So I can learn a lot from this thread. I need to check my injector flow (as shown in the shop manual). I'll probably do that when I replace my injector seals soon.
I'm also assuming vacuum leaks can cause big fuel consumption problems, with the ECU fluctuating the mix thinking it's too lean or something like that. So after I replace the injector seals, I'm certainly going to be using this thread.
So thank you for your reply.
I'm also very interested to hear the results from the original poster.
I am glad somebody caught my humor in all this.
My aplologies for assuming too much here, given the O P did not give enough detail and never checked it, or even looked under the car until so suggested by several people.
All I am saying is that the new fuel pump has multiplied his problems with the obviously old F I system.
Injectors were probably leaking before and now they're gushing with the extra pressure.
But don't take my word for it. Let the O P give you more details and then ....eventually tell you what the probllem was and how it got fixed.
I am personally dying to hear the end of this, if he can first of all manage to change the oil....
Good luck all, my bad of course.:surrender:
Hey Punkt: FYI I tried to send you a PM but it was refused. We're nice folks in here and generally all like each other (I think). I don't think there's much of anybody getting upset around here. Hopefully LostViet408 is going to be OK. I've got my fingers crossed for him.
As for why he's not gotten back to you on the stuck injector, He's probably simply busy with other things, and hopefully his car is sitting in his mechanic's garage. I don't blame the guy for not testing the injectors. It ain't easy if:
- you don't have the service manual
- you don't have someone else to crank the ignition for you
- you don't have an apparatus (maybe as simple as a house gutter) to catch the fuel
Just because someone is on this site doesn't mean they're a mechanic. But we do expect them to be able to read. I think the guy know's he's got fuel in his oil and has read your post. Hopefully he's told his mechanic.
I think we are all waiting to hear what kind of damage this does to your engine. Hopefully not too much. Hopefully we will find out.
BTW: If anything I said above comes across negatively, please excuse me. I'm just trying to explain from the point of view of a novice.
-------------------------
Meanwhile, I did my first highway road test to check fuel consumption in my car (inspired by this thread). I had only been getting about 5 mpg with city and lots of idling while working on the car. Tonight I got between 16 and 18 mpg on a 40 mile flat highway ride with nearly NO brakes at ~2500 rpms and ~60-65 mph. I'm pretty happy to realize that after all my 5 mpg fills over the last 8 months of the car sitting around. I was starting to think I had a real pig on my hands. Shwew!
Now let's hope LostViet408 gets good news from the mechanic (or decides to get some serious gumption and diagnose this himself... with our help of course).
I figure you can lead a horse to water, but can't make it drink.
I tried to fix the PM thing.
This whole message board is so complex and memory hogging, it's also hard to manoever.
Your input is well received and I wasn't directing anything against you, if it seemed that way....
Glad to hear you've come out ahead with better mileage.
Now I'd like to find somebody, who could tell me how I can get more than 24mpg with my 300CD ...............
Cheers
Alex
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